Stated before: only two pallets can be shipped to one address at a time. That's why they're at different locations.
..and in what amounts to about 25 years of being exposed to shipping in one way or another, with a vast amount of years dealing with container loads, LTL, a few pallets, odd shaped stuff, etc.
I have -never- once, -ever- heard of ANY kind of limitation on what quantity of units I can deliver -anywhere- based on anything other than the actual facility itself where the delivery is taking place.
If they can unload one pallet, they can unload 10 of them. That's what they're paid to do. Deliver stuff. If there's a surcharge for lift gate, there's a surcharge for it. But once the pallet is off the truck, on the ground, the delivery vendor has done it's job.
There's no ordinance restricting deliveries. What if you bought a swing set that came on six pallets? Some do. "nope, sorry, you gotta bring two of them to one each of my neighbors."
Two pallet limit? Fine. Deliver two today, in another couple days.. since it will take you that long to break it down and re-label for shipment, because if not, why is the "limit" an issue in the first place, since you could just be using freight forwarding, which any volume seller knows full well that they can deliver straight to the dock of whoever is the next shipper.
Which brings me to the $900/mo UPS holding fee? That's another -never- heard of it. The only holding UPS does is fulfillment. As an example, ever wonder how you can order a phone from Sprint until insane hours of the evening and still get it in the morning? Because the phones are actually stocked at the UPS hub, pre-boxed for individual dispatch. Slap a label on it, inject the parcel into automation, just like if it got there on the plane from the pickup location. Otherwise.. anything else, they're not in that business. They'll accept freight, and forward it. When it gets there.
They don't want to store your stuff. They want to deliver it. They are not called United Parcel Storage.